Results 1 to 10 of about 1,919 (235)

Gemini Near Infrared Spectrograph–Distant Quasar Survey: The Chandra View

The Astrophysical Journal
We present Chandra observations of 63 sources from the Gemini Near Infrared Spectrograph−Distant Quasar Survey, of which 54 were targeted by snapshot observations in Cycle 24.
Andrea Marlar, Ohad Shemmer, Michael S. Brotherton, Gordon T. Richards, Cooper Dix, Brandon M. Matthews, W. N. Brandt, R. M. Plotkin   +7 more
doaj   +1 more source

Active galactic nuclei. 5: X-ray variability and the black hole cluster paradigm

, 1994
A. G. Pacholczyk, W. R. Stoeger
openalex   +1 more source

Local supermassive black holes, relics of active galactic nuclei and the X-ray background [PDF]

, 2004
A. Marconi, G. Risaliti, R. Gilli, L. K. Hunt, R. Maiolino, M. Salvati   +5 more
openalex   +1 more source

SAX J1808.4--3658 and the origin of X-ray variability in X-ray binaries and active galactic nuclei [PDF]

, 2004
P. Uttley
openalex   +1 more source

Black hole mass estimation from X-ray variability measurements in active galactic nuclei [PDF]

, 2004
M. Nikołajuk, I. E. Papadakis, B. Czerny   +2 more
openalex   +1 more source

Active galactic nuclei and X-ray observations [PDF]

Journal of Physical Studies, 2016
A. A. Vasylenko, E. V. Fedorova, V. I. Zhdanov   +2 more
openaire   +2 more sources

Pure scattered emission as an explanation for the hard X-ray spectra of active galactic nuclei

, 1995
E. Jourdain, J. P. Roques
openalex   +1 more source

The Fall of Active Galactic Nuclei and the Rise of Star-forming Galaxies: A Close Look at the Chandra Deep Field X-Ray Number Counts [PDF]

, 2004
F. E. Bauer, D. M. Alexander, W. N. Brandt, Donald P. Schneider, Ezequiel Treister, A. E. Hornschemeier, G. P. Garmire   +6 more
openalex   +1 more source

Changing-look Active Galactic Nuclei: A Study of Optical/UV and the Highly Ionized Fe Kα X-Ray Line Flux Variations Using Photoionization Simulations

The Astrophysical Journal
Significant variability in broad emission line strengths of active galactic nuclei (AGN) over months to years has been observed, often accompanied by intrinsic continuum changes.
Tek P. Adhikari, Santanu Mondal, Zhicheng He, Agata Rozanska, Krzysztof Hryniewicz   +4 more
doaj   +1 more source

Powerful, obscured active galactic nuclei among X-ray hard, optically dim serendipitousChandrasources [PDF]

, 2004
P. Gandhi, C. S. Crawford, A. C. Fabian, R. M. Johnstone   +3 more
openalex   +1 more source